The San Francisco Giants have posted four consecutive shutout wins for the first time in franchise history.
Giving the ball to Matt Cain could help the NL West leaders extend their remarkable streak.
Cain will try to help the Giants win a season-high fifth straight game Friday night as the NL Central-leading Cincinnati Reds look to avoid their first five-game road skid in more than a year.
After outscoring the Los Angeles Dodgers 13-0 in a three-game sweep that moved them into a first-place tie, the Giants (44-33) are alone atop the West for the first time since Aug. 9 following Thursday's 5-0 win over the Reds (41-34) and the Dodgers' 3-2 loss to the New York Mets.
"That's a pretty good streak they're on," Reds manager Dusty Baker said after his club was one-hit for the first time since July 29, 2009, against San Diego.
Cain (9-2, 2.27 ERA) could help the Giants to their first five-game win streak since an eight-game run Sept. 11-18.
The right-hander is coming off a no-decision in Sunday's 4-2 loss at Oakland. Pitching for the second time since he threw the majors' 22nd perfect game June 13 against Houston, Cain allowed just one run and three hits in seven innings but had his career-best streak of eight consecutive winning starts end when Derek Norris hit a three-run homer off Santiago Casilla.
Those were the most recent runs allowed by Giants pitching.
"To get walked off by anyone, it's not a good feeling," said Cain, among the NL leaders with 107 strikeouts and 107 innings.
He couldn't have felt too good about a 9-2 loss at Cincinnati on April 24, when he allowed three runs on two homers in 6 1-3 innings.
Brandon Phillips hit a two-run shot off Cain in that contest, but the All-Star second baseman may miss a second straight game Friday after he was tested for a concussion following a collision with Milwaukee's Aramis Ramirez on Wednesday.
"He has to feel better to play," Baker told the Reds' official website. "We've got Cain tomorrow, who throws about a thousand (mph)."
The Reds will counter with Mike Leake (2-5, 4.46), who is 2-0 with a 2.82 ERA in his last eight outings after throwing eight strong innings in Sunday's 4-3 loss to Minnesota. He was removed after throwing just 86 pitches, and Reds closer Aroldis Chapman allowed a two-run ninth-inning homer.
"Leake just came off throwing 112 (actually 114) pitches his last time out," Baker said. "... What if I send Leake out and he gives it up? The hitters coming up would have seen him for the fourth time."
Three batters have faced Leake four times in a game in 2012, and none got a hit the fourth time. Still, Baker should be careful if Leake gets deep into Friday's game, as the Giants are batting .338 when they see a pitcher for at least the fourth time.
Leake might not be looking forward to seeing Pablo Sandoval in any inning. The third baseman has five hits -- including a homer -- in seven at-bats against the right-hander.
Buster Posey is 3 for 4 with a homer off Leake, who is nonetheless 2-0 with a 2.89 ERA in three starts versus San Francisco.
The Reds' last five-game slide outside Cincinnati was May 11-23, 2011.
Copyright 2012 by The Associated Press
This story is from ESPN.com's automated news wire. Wire index
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